Ability of Different Treatments of Saccharomyces cerevisiae to Surface Bind Aflatoxin M 1 in Yoghurt

Abstract:

Microbial detoxification is considered as one of th
e most common methods used for the
elimination of aflatoxins. Reports indicate that
S. cerevisiae
can be effective in removing
aflatoxins through the adsorption of aflatoxins to
their cell wall. In the current research,
the ability of
S. cerevisiae
(viable, acid-, heat- and ultrasound-treated yeast
s) to bind
aflatoxin M
1
was assessed in yoghurt. To this end, firstly, rec
ombinant milk containing
12% solids, non-fat skimmed milk powder was prepare
d. Next, the samples were spiked
by aflatoxin M
1
using different concentrations (100, 500 and 750 p
g mL
-1
). When the
starter bacteria were added to the milk, the treate
d yeasts were added as well. The
concentration of aflatoxin M
1
residue in the supernatant of the yoghurt samples
after
different storage times (1, 7, 14 and 21 days) was
measured using the ELISA method. The
results showed that all treatments containing viabl
e, acid-, heat-, ultrasound-treated yeast
and starter bacteria were able to adsorb aflatoxin
M
1
, and the ability of the treated yeast
was significant as compared with the control (P< 0.
05). Among the treated yeasts, the
ability of the acid-treated yeasts was higher in to
xin binding. Overall, it can be concluded
that using
S. cerevisiae
for the biological adsorption of aflatoxin M
1
is effective in
fermented dairy products.
Keywords:
Biological adsorption, Cell wall, Fermentation, Man
nan,
Yeast.